Chapter 21: Audio/Visual Devices^547
are literally cut off, which produces distortion in the playback. This is why sound
capture software includes some form of visual recording level gauge.
Sample rate Although it is expressed in kilohertz (kHz), the sample rate is the
distance between samples captured in a sound file. So, indirectly the sample rate
refers to the number of samples, or short bites of the sound, that are taken from
the audio in a second. The sample rate used by CD-quality sound is 44.1 kHz,
and it produces good results for most applications. Audio recorded for pro-
fessional applications may be sampled at a higher rate to increase fidelity and
provide more headroom for audio editing. Lower sample rates will use less
disk space at the cost of audio quality. The maximum and minimum sample
rate available is subject to the limitations of both the sound card and the soft-
ware being used. The standard Windows Sound Recorder provides you with
slide controls that allow you to balance the sound file’s playback quality to its
disk size on its advanced features tab, shown in Figure 21-3.
Sample resolution Expressed in bits, sample resolution refers to the size of the
samples taken. CD audio is stored at a resolution of 16 bits. This means that 16 bits
of binary data are used to describe the sound that should result from the sample
being analyzed by the sound card and DSP. Sample resolution involves the same
trade-offs with regard to file size and sound quality that apply to sample rate.Figure 21-3. The Windows Sound Recorder’s advanced features settings